Krugman, Paul R., author
Scott, Foresman, 1988
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Salvatore, Dominick, author
Prentice-Hall, 1995
Buku Teks
Salvatore, Dominick, author
John Wiley & Sons, 2007
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Hasna Alifa, author
2019
UI - Skripsi (Membership)
Vernon, Raymond, author
Prentice-Hall, 1981
Buku Teks